A circuit breaker is an automatically operated electrical switch designed so that they can  protect the electrical circuits from getting damage due to excessive flow of current.Different types of circuit breaker are:

• Air Magnetic Circuit Breakers.
• Air Blast Circuit Breakers.
• Oil Circuit Breakers.
• Sulfurhexafluoride (SF ₆ ) Circuit Breakers.
• Vacuum Circuit Breakers

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